Oilpan: Ensure that classes with virtual trace methods always have vtables for their left-most base…

Source/core/dom/ExecutionContext.cpp

Index: Source/core/dom/ExecutionContext.cpp
diff --git a/Source/core/dom/ExecutionContext.cpp b/Source/core/dom/ExecutionContext.cpp
index 115cad2495075ef2a787419b80509d34e13b0e91..34a629b3fae3353b5f74a790399d27708b448106 100644
--- a/Source/core/dom/ExecutionContext.cpp
+++ b/Source/core/dom/ExecutionContext.cpp
@@ -328,7 +328,8 @@ void ExecutionContext::trace(Visitor* visitor)
 #if ENABLE(OILPAN)
     visitor->trace(m_pendingExceptions);
 #endif
-    WillBeHeapSupplementable<blink::ExecutionContext>::trace(visitor);
+    WillBeHeapSupplementable<ExecutionContext>::trace(visitor);
+    LifecycleContext<ExecutionContext>::trace(visitor);
 }
 
 } // namespace blink